Chapter 17 Flashcards
occur when the second pharyngeal arch fails to grow caudally over the third and fourth arches, leaving remnants of the second, third, and fourth clefts in contact with the surface by a narrow canal
Branchial Fistulas
a fistula, found on the lateral aspect of the neck directly anterior to the sternocleidomastoid muscle, usually provides drainage for a lateral cervical cyst
Branchial Fistula
cysts that are remnants of the cervical sinus, are most often just below the angle of the jaw, although they may be found anywhere along the anterior bor- der of the sternocleidomastoid muscle.
Lateral cervical cyst
are rare; they occur when the cervical sinus is connected to the lumen of the pharynx by a small canal, which usually opens in the tonsillar region
Internal branchial fistulas
fistula resulting from a rupture of the membrane between the second pharyngeal cleft and pouch at some time during development.
Internal brachial fistula
Cells that are essential for formation of much of the craniofacial region.
Neural crest cells
septate the outflow tract of the heart into pulmonary and aortic channels
Conotruncal endocardial cushions
The syndrome is characterized by hypoplasia of the maxilla, mandible, and zygomatic arches, which may be absent.
Treacher Collins Syndrome (mandibulofavial dysostpsis
Mutations of whhic gene are responsiple for the Treacher Collins syndrome
TCOF1 gene (5q32)
The product of TCOF1 gene that appears to be necessary for preventing apoptosis and maintaining proliferation in neural crest cells but not for regulating their migration, which occurs normally.
Treacle
Exposure to which teratogenic can produce phenocpies of the treacle
Retinoic acid
may occur independently or in association with other syndromes and malformations. Like Treacher Collins syndrome, this sequence alters first-arch structures, with development of the mandible most severely affected.
Robin sequence
posteriorly placed tongue]
Glossoptosis
is the most common deletion syndrome in humans and has several presentations, including DiGeorge syndrome, DiGeorge anomaly, ve-locardiofacial syndrome, Shprintzen syndrome, conotruncal anomaly face syndrome, and congenital thymic aplasia and hypoplasia.
22q11.2 Deletion syndrome
Mutations in what gene result in the same syndrome (2aq11.2 Deletion syndrome) without a deletion
TBX1
cells from the pouches that make the thymus and parathyroid cells
Endpderm cells
Includes a number of craniofacial abnormalities that usually involve the maxillary, temporal, and zygomatic bones, which are small and flat.
Hemifacial microsomia [oculoauriculovertebral spectrum or Goldenhar syndrome]
the tongue is not freed from the floor of the mouth.
Ankyloglossia (tongue-tie)
the only tissue that anchors the tongue to the floor of the mouth
Frenulum
may lie at any point along the migratory pathway of the thyroid gland but is always near or in the midline of the neck.
Thyroglossal cyst
it is a cystic remnant of the thyroglossal duct.
Thyroglossal cyst
fistula usually arises secondarily after rupture of a cyst but may be present at birth.
Thyroglossal fistula
may be found anywhere along the path of descent of the thyroid gland. It is commonly found in the base of the tongue, just behind the foramen cecum, and is subject to the same diseases as the thyroid gland itself
Aberrant thyroid tissue
Are common defects that result in abnormal facial appearance and difficulties with speech
Cleft lip and cleft palate
considered the dividing landmark between anterior and posterior cleft deformities.
Incisive foramen
include lateral cleft lip, cleft upperjaw, and cleft between the primary and secondary palate
Anterior to the incisive foramen
Such defects are due to a partial or complete lack of fusion of the maxillary prominence with the medial nasal prominence on one or both sides.
Those anterior to the incisive foramen
include cleft [secondary] palate and cleft uvula
Lie posterior to the incisive foramen
results from a lack of fusion of the palatine shelves, which may be due to small- ness of the shelves, failure of the shelves to elevate, inhibition of the fusion process itself, or failure of the tongue to drop from between the shelves because of micrognathia
Cleft palate
the most com- mon syndrome associated with cleft lip with or without cleft palate
Van der Woude syndrome
Mutated genes in the van der woude syndrome
Interferon regulatory factor 6
produced by failure of the maxillary prominence to merge with its corresponding lateral nasal prominence along the line of the nasolacrimal groove. When this occurs, the nasolacrimal duct is usually exposed to the surface
Oblique facial clefts
a rare abnormality, caused by incomplete merging of the two medial nasal prominences in the midline
Median (midline) cleft lip
Loss of midline tissue may be so extensive that the lateral ventricles fuse resulting to
Holoprosencephaly
occurs more frequently in males [65%] than in females, and its incidence varies among populations. Asians and Native Americans have some of the highest rates [3.5/1,000], whereas African Americans have the lowest [1/1,000].
Cleft lip with or without cleft palate
occurs more often in females [55%] than in males; In females, the palatal shelves fuse approximately 1 week later than in males,
Isolated cleft palate
erupted by the time of birth. Usually, they involve the mandibular incisors, which may be abnormally formed and have little enamel.
Natal teeth
Cause of discoloration of the teeth
Tetracyclines
deficiency in enamel is often caused by
Vitamin D deficiency
